Spirometry is a recommended component of asthma diagnosis and treatment in the primary care setting, yet few providers report its routine use for children with asthma. Misclassification of asthma severity occurs when assessment is based on symptoms alone. This misclassification can lead to inadequate treatment, increased morbidity, and increased healthcare utilization/cost. The goal of this study is to test the effectiveness of a distance learning quality improvement program called Spirometry 360 developed by the interactive Medical Training Resources (iMTR) group at the University of Washington Child Health Institute. The Spirometry 360 program aims to improve care for children with asthma by enhancing provider knowledge and self-efficacy related to the use and interpretation of office-based spirometry. The Spirometry 360 program includes: 1) Spirometry Fundamentals: A basic guide to lung function testing, a computer-based training program that teaches primary care providers how to: a) coach patients to produce high-quality spirometry tests and b) accurately interpret spirometric data; 2) Spirometry Learning Lab: Case-based teaching of spirometry in practice guides test administrators and interpreters through clinical examples in an interactive virtual classroom setting. These sessions are led by expert clinical faculty and are archived for future reference and review. 3) Spirometry Feedback: Tailored analysis of providers' spirometry testing sessions offers monthly individualized feedback reports by clinical experts on spirometry tests performed in the clinic. To test the effectiveness of the Spirometry 360, we will conduct a randomized controlled trial in 50 primary care pediatric practices throughout the United State. Twenty-five practices will receive the full Spirometry 360 program. A separate group of 25 matched control practices will receive standard spirometry training from the equipment vendor. Quality of care at the practice level will be measured by examining the quality of spirometry testing sessions and the frequency of appropriate controller medication use in intervention versus control practices. Quality of care at the patient level will be assessed by examining asthma-specific health related quality of life, numbers of unplanned visits for asthma exacerbations, hospitalizations due to asthma, and costs of asthma care. If the Spirometry 360 program proves to be an effective approach to improving healthcare for children with asthma, we anticipate it could be widely disseminated to healthcare providers nationally. PUBLIC HEALTH RELEVANCE: This study will be the first of its kind to rigorously test whether using spirometry in the management of children with asthma actually results in improved asthma-related outcomes for these children. Building a body of evidence that links high quality processes of care to desired outcomes of that care is a first critical step in convincing primary care providers to follow recommendations related to these care processes. If our proposed intervention increases provider utilization of spirometry as recommended by the National Asthma Education and Prevention Program and leads to improved health-care outcomes for children with asthma, we anticipate it could be widely disseminated to health care providers and thus reduce asthma related morbidity on the national level.